patch-2.1.15 linux/drivers/scsi/README.dtc3x80

Next file: linux/drivers/scsi/README.ncr53c8xx
Previous file: linux/drivers/scsi/README.AM53C974
Back to the patch index
Back to the overall index

diff -u --recursive --new-file v2.1.14/linux/drivers/scsi/README.dtc3x80 linux/drivers/scsi/README.dtc3x80
@@ -6,15 +6,17 @@
 Data Technology Corp---a division of Qume.
 
 The 3280 has a standard floppy interface.
+
 The 3180 does not.  Otherwise, they are identical.
+
 The DTC3x80 does not support DMA but it does have Pseudo-DMA which is
 supported by the driver.
+
 It's DTC406 scsi chip is supposedly compatible with the NCR 53C400.
-It is memory mapped, uses an IRQ, but no dma or io-port.  There is 
+It is memory mapped, uses an IRQ, but no dma or io-port.  There is
 internal DMA, between SCSI bus and an on-chip 128-byte buffer.  Double
-buffering is done automagically by the chip.
-Data is transferred between the on-chip buffer and CPU/RAM via
-memory moves.
+buffering is done automagically by the chip.  Data is transferred
+between the on-chip buffer and CPU/RAM via memory moves.
 
 The driver detects the possible memory addresses (jumper selectable):
 	CC00, DC00, C800, and D800
@@ -24,21 +26,20 @@
 Information can be obtained from /proc/scsi/dtc3c80/N.
 
 Note on interrupts:
+
 The documentation says that it can be set to interrupt whenever the
-on-chip buffer needs CPU attention.  I couldn't get this to work.
-So the driver polls for data-ready in the pseudo-DMA transfer routine.
+on-chip buffer needs CPU attention.  I couldn't get this to work.  So
+the driver polls for data-ready in the pseudo-DMA transfer routine.
 The interrupt support routines in the NCR3280.c core modules handle
-scsi disconnect/reconnect, and this (mostly) works.
-However.....
-I have tested it with 4 totally different hard drives (both SCSI-1 
-and SCSI-2), and one CDROM drive.
-Interrupts works great for all but one specific hard drive.  For this one,
-the driver will eventually hang in the transfer state.
-I have tested with: "dd bs=4k count=2k of=/dev/null if=/dev/sdb".  It
-reads ok for a while, then hangs.  After beating my head against this for a
-couple of weeks, getting nowhere, I give up.
-So.....This driver does NOT use interrupts, even if you have the card 
-jumpered to an IRQ.  Probably nobody will ever care.
-Nor will I when the $380 2.5GB IDE drives hit the market in early 1996!
+scsi disconnect/reconnect, and this (mostly) works.  However.....  I
+have tested it with 4 totally different hard drives (both SCSI-1 and
+SCSI-2), and one CDROM drive.  Interrupts works great for all but one
+specific hard drive.  For this one, the driver will eventually hang in
+the transfer state.  I have tested with: "dd bs=4k count=2k
+of=/dev/null if=/dev/sdb".  It reads ok for a while, then hangs.
+After beating my head against this for a couple of weeks, getting
+nowhere, I give up.  So.....This driver does NOT use interrupts, even
+if you have the card jumpered to an IRQ.  Probably nobody will ever
+care.
 
 

FUNET's LINUX-ADM group, linux-adm@nic.funet.fi
TCL-scripts by Sam Shen, slshen@lbl.gov